Your reader's mindset is contentious from the get-go, and they're going to want to prove you wrong if statement is controversial. It doesn't bode well for your point if you can't convincingly back it up.
The true point in this article is that visual cues within UIs are great and nice. It's a huge victory when you can educate your user naturally (see: the popular Super Mario Bros example), but it just doesn't apply to everything. Not everything is innate; some new things need to be taught. How do we learn most things? We observe someone doing the same thing.